Would it have been realistic for either Spain or Portugal to conquer some or all of North Africa after the end of the Reconquista in 1492?
Also, for the record, I am talking about more than a mere conquest here; specifically, I am talking about having Spain/Portugal successfully Chrisitianize the parts of North Africa that they conquer just like Spain previously did with Grenada (albeit certainly not in a very pleasant fashion!).
The Spanish and Portuguese did as good as they could OTL, anything more that lasts is on the fringe of ASB.
Well, they did manage to take over the predominantly-Muslim Granada. But Africa is more difficult.
Some thoughts:
Columbus's mission to the Americas fails. If other missions are tried, they also fail. People will generally just assume that it's too far to go round the globe west to the East Indies, and the discovery of the New World might be delayed quite a bit. I don't know how long it can be delayed for.
Lack of New World knowledge means the Spanish/Portuguese can focus on Africa and the Cape route to India instead.
Dynastic union between the two countries to avoid conflict on the Iberian peninsula.
Now. For the challenge. Aim for weakest nation on the North African coast. Tunisia might be weaker than Morocco.
Can you conquer inland area somewhere? I'm not certain.
If necessary, you could always try to win the loyalty of the Jews with the intent of backstabbing them later.
If you get some inland space in Africa: massacre all circumcised males in conquered land. Settle down the war veterans here. They take all the recently-widowed local women. Build up a strong, large, and powerful base of Christians there. Chances of losing it again are greatly diminished.
Once you have a bit of land like that (inland Tunisia), it becomes easier. That's your base. Just keep slowly expanding, massacring Muslims and putting a lot of Christians in the newly-won territories.
With Colombus' failure there bound to be a discovery of America within the next few decades by drifting from the African route to Brazil.
A solid dynastic union could be accomplished through Miguel de Aviz's survival, but even that's not enough to make North African conquest viable.
Getting rid of the Jewish population of Spain was one of the greatest mistake ever made by the Spanish monarchy. The Jews of Spain were the closest thing to a middle class that Castille had and they formed a significant amount of the middle class in Aragon. Their removal stagnated Spain's economic development for centuries.
Genocide is not easy to perform in the 15th and 16th century. In the Americas it occurred due to the outbreak of disease, disease which North Africans are not so susceptible to. Also in the Americas intermarriage with the Amerindians was common because the Amerindian wives were converted. Conversion of the North American female population to Christianity is just not happening, especially after the Christians just massacred their husbands.
Conquering this "inland" is far harder than you imagine. The major cities were usually many miles from the coast and the area in between was either filled with Muslims or filled with hostile terrain.
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